Plastic tethered aerial top



May 25, 1965 J. J. PETRUCELLI ROTATING HEAD-CARRIED TOY Filed April 4, 1963 g wm ATTORNEYS INVENTOR JILIO J. PETRUCELLI May 25, 1965 J. E. GIBSON, JR 3,184,885

' PLASTIC TETHERED AERIAL TOP Filed Feb. 6, 1963 2 Sheets-Sheet 2 INVENTOR W 6 J mar Gibsm/F:

BY ATTORNEY United States Patent 3,184,885 PLASTIC TETHERED AERIAL TOP James E. Gibson, Jr., High Point, N.C.; Wachovia Bank 8: Trust Co., executor of said James E. Gibson, in,

deceased Filed Feb. 6, H63, Ser. No. 256,745 8 Claims. (Cl. 46-61) This application is a continuation-in-part of my copendingapplication, Serial No. 183,854, filed March 30, 1962, and entitled Plastic Yo-Yo.

This invention relates to Yo-Yos and is particularly concerned with Yo-Yos made primarily from moldable plastic material, as well as Yo-Yos made exclusively from moldable plastic material.

As well known to those familiar with Yo-Yos, the same generally comprise a whirlable body disposed at one end of a comparatively long cord. The body comprises a pair of generally disc-shape members having opposed spaced apart inner faces. The disc members are maintained in such spaced relationship by means of a central pin traversing the space between the members, and about which one end of the string or cord is looped.

Yo-Yos conforming with the construction described in the immediately preceding paraghaph have previously been made from wood or plastic and metal components. With the wood constructions the disc-shape end members are generally turned on a lathe and joined together by a wooden pin extending between and within bores centrally disposed in the inner faces of the end members. For production purposes, the end members are generally mass produced, mixed with other end pieces, and thereafter separated and joined together by the pins. With the wood construction, there is a tendency of the finished product to become distorted due to shrinkage after fabrication with the result that the central cord receiving channel between the end members is not maintained uniform. Moreover, because of the production techniques required to produce the wood Yo-Yo at a competitive price, there is often a difference in weight of each of the end members and a difference in diameter. Matching respective end members whereby any pair is selected from a single initial piece of stock and the same turning operation would be unduly expensive,.and thus the Wood Yo-Yos from a practical standpoint are subject to all of the disadvantages set forth in this paragraph.

Apparently realizing the deficiencies with the wood construction, it has previosuly been suggested that the Yo-Yos be formed at least partially of plastic. hi accordance with the most practical of the previous suggestions along this line, four separately fabricated molded plastic components are provided and a solid metal pin, normally aluminum, is used to join the pieces together to provide the Yo-Yo body. The solid metal pin is knurled at opposite ends thereof and is adapted to frictionally engage respective components to supposedly maintain the same in the desired relative position thereof. Manufacture of Yo-Y-os of the type discussed in this paragraph also results in certain problems. First, manufacture is expensive due to the number of parts which must be assembled, and due to the alignment which must be maintained. Moreover, the solid aluminum pin serves as the central shaft, and with the inherent friction existent between such pin and the Yo-Yo string or cord, the pin becomes heated. Due to the solid construction thereof, the frictional heat generated is not readily dissipated, and with the arrangement of the other parts, proper or quick heat transfer from the pin is not, and cannot be, accomplished.

It should be apparent from the preceding discussion that there remains a need for a Yo-Yo which can be easily assembled from a minimum number of components to provide an ultimate Yo-Yo body which is Well balanced and which does not otherwise have the disadvantages of prior constructions.

Consistent with the above, two primary objects of the present invention are (a) to provide an improved Yo-Yo construction wherein the body thereof is formed solely and exclusively from plastic materials of the type which readily lends itself to molding operations, and (b) to provide an improved Yo-Yo construction wherein the body thereof is formed from moldable plastic components and a single metal component in such manner that the metal component is molded in position with the plastic base components and wherein the metal component and associated plastic components are so arranged as to provide for efficient heat dissipation.

Still a further important object hereof is to provide a basic Yo-Yo construction having either a phase central pin or a hollow metal central pin, and which is completely balanc d about the rotational axis thereof. Further, an important object hereof is to provide such a Yo-Yo construction which is durable with continued use under the normal taxing operating conditions.

Additional, yet further, and more specific objects of the present invention include the following: (a) the provisic-n of a Yo-Yo body conforming with the preceding discussion which comprises three easily joined and easily molded components which are shaped and contoured so as to matingly and frictionally engage one another in such a manner as to provide for automatic alignment therebetween; (b) the provision of such a Yo-Yo body which incorporates frictionally engageable components, but which provides means for effectively welding the components together in indestructible relation by means of a bonding resin, such as, for example, epoxy resin, (0) the provision of such a Yo-Yo body which comprises a pair of cover members and a unitary core member, the core member having peripheral edges adapted to conformingly mate with peripheral recesses in the cover members so as to frictionally lock the cover members in end covering relationship on opposite sides of the core memher; and (d) to provide such a Yo-Yo body incorporating a core member having tapered peripheral edges which permit automatic central insertion thereof within recesses disposed adjacent the periphery of the cover members and adapted to receive such peripheral edges.

Consistent with one embodiment hereof, still further primary objects of the present invention are specifically: (a) the provision of a Yo-Yo body conforming with the preceding discussion, which body has a central channel therein about the rotational shaft thereof that is of uniform cross-section throughout its depth and not subject to deformation with variations in atmospheric conditions or periods of storage; and (b) to provide such a Yo-Yo body which has a central shaft therein shaped to direct the cord associated therewith centrally of the body so as to provide for automatic alignment of the cord with the center of gravity of the body during use.

Consistent with another embodiment hereof, a primary specific object of the present invention is to provide a plastic Yo-Yo body having a hollow aluminum central shaft and cooperating body members which provide for dissipating the heat generated in the shaft in directions away from the shaft whereby to prevent undesired expansion and/or other changes in the body with continued operation of the Yo-Yo.

The invention lies in. the combination, construction, arrangement and formation of the various components constructed in accordance herewith. The invention will be better understood, and objects other than those set forth above will become apparent, when consideration is given to the following detailed description. Such description refers to the annexed drawings presenting preferred and illustrative embodiments of the invention. In the drawings:

FIGURE 1 is a perspective view of a Yo-Yo constructed in accordanw with the present invention;

FIGURE 2 is a sectional view of the Yo-Yo shown in FIGURE 1;

FIGURE 3 is an exploded view of the components incorporated in the Yo-Yo shown in FIGURES l and 2;

FIGURE 4 is a perspective View, similar to FIGURE 1, but presenting a Yo-Yo constructed in accordance with a modification of the present invention;

FIGURE 5 is a sectional view of the Yo-Yo shown in FIGURE 4, FIGURE 5 illustrating the details of one modified embodiment thereof;

FIGURE 6 is an exploded View illustrating another modified embodiment thereof, and

FIGURE 7 is a perspective view of the center post element incorporated in the modified embodiments of FIGURES 5 and 6.

To facilitate consideration of the respective embodiments of the invention, attention is initially directed to the all-plastic unit shown in FIGURES 1 through 3 and constituting a preferred embodiment hereof. Thereafter, consideration is given to the modified embodiments of FIGURES 4 through 7. The modified embodiments are in basic respects identical with the preferred embodiment, and thus a full understanding of the preferred embodiment simplifies comprehension of the changes made consistent with the modified embodiments.

The preferred embodiment If reference is now made to FIGURE 1, it will be noted that the Yo-Yo body there shown is generally designated by the numeral 2. Such body is carried about the lower end of theYo-Yo cord 4. The upper end of the cord 4- is formed into a loop 6 through which the users finger can be passed.

As conventional, and as shown in FIGURE 2, the lower end of the cord 4 is passed about the central shaft or shaft member 10 of the Yo-Yo. The cord 4, as also conventional, preferably comprises a single long strand of cord of suitable weight, which strand is doubled over about the shaft member 10 and then twisted thereabove to the opposite end thereof.

In use, the cord 4 is initially wrapped about the shaft member 10 and within the channel 12 of the Yo-Yo body 2 with at least the finger loop 6 extending therebeyond. Then, the operator lowers the Yo-Yo body 2 with the loop about the users finger, and the body rotates during descension and ultimately is supported at the lower end or doubled-over end of the cord 4. A familiar operator may allow the body to rotate in the descended posi tion, i.e., allow the body to sleep. In any event, after descension, an upward jerk on the finger engaged by the loop 6 causes the Yo-Yo body to return to the operators hand for a subsequent operation. Of course, various tricks can be performed with the Yo-Yo as is well known.

By virtue of the nature of the toy or device, and the intended use thereof, it is particularly desirable that the body be balanced for rotation about the shaft member thereof and that the body channel 12 be uniform in cross-section and not distorted in any way. Moreover, it is important that the shaft member 10 offer as low resistance as possible to rotation in the lower loop of the cord 4, and abrade the cord during rotation as little as possible. 7

One additional particularly important factor relates to the components and material from which the body 2 is made. Specifically, as few components as possible should be incorporated to facilitate production, and the components should be formed from a material and in a manner which. insures uniformity.-

In accordance with the invention, all of the desirable aspects mentioned above are achieved by making the body components as molded units from a suitable plastic, such as, for example, polyethylene or polypropylene. In fact, ithas been found that polystyrene may be particularly desirable due to the high durometer which can be obtained therewith.v It isto be understood that the plastics herein suggested are exemplary, and any other suitable plastic can housed in accordance with the invention. 7

Now, if reference is made to FIGURE 3, it will be noted that in accordance with the invention only three components are used to form the Yo-Yo body 2. Specifically, first and second plastic cup-shaped cover members 20 and 22 are provided, and secondly an integral core member 24 is incorporated to cooperatively engage the cover members 20 and 22 to form the body.

The cover members 20 and 22 are substantially identical and thus the cover. member 20 only is described in detail in the following paragraphs. Prime numerals have been applied to the cover member 22 to correspond with the numerals used'in the description of the cover member-2il and to eliminate any misunderstanding.

The cover member 20 has an at least substantially planar and generally circular base 39. An arcuately shaped upstanding ring skirt 32 is formed integrally with the base 30. The skirt 32 has an inwardly opening-recess 34 in the interior wall 36 thereof. The recess 34 is adjacent the peripheral or inner edge 33 of the skirt 32, i.e., the edge thereof remote from the base 30.

The recess 34 terminates :at an inwardly extending shoulder or rib 49 disposed substantially parallel to the base 30. The cover member 20 further includes an inwardly extending post 42 which is formed integrally therewith. The post is centrally disposed on the base 30 and within the skirt 32. The terminal end 44 of the post 42 lies in a plane which isdisposed between the shoulder 40 and the peripheral edge 38 of the skirt portion'32. Such plane is designated by the letter P in' FIGURE 3.

The cover member 22 is of identical construction, as suggested above, but in the'ultimate unit is faced in the opposite direction so that the outside face of the base 30' thereof is disposed remote from the outside face of the base 30 of the cover member 20.

It will be readily appreicated by those of ordinary skill in the art that the cover members 20 and 22 have a design which readily permits theform ation thereof by mass production techniques such as in an injection molding machine.

Now, as indicated in the preceding paragraphs, the cover members 20 and 22 are designed to cooperatively associate with the core member 24. The core member, as shown in FIGURE 3 comprises first and second discs generally indicated by numerals 5i and 52 which are disposed in spaced apart relation. The central shaft member ltl'is integral with the discs 56 and S2 and traverses the space or channel 12 between the discs. The shaft member ltlhas a concave surface contour as indicated at 54. In effect, the concave contour of the shaft member 10 forms a groove extending about the entire periphery thereof. This groove directs the lower. end of the string or cord 4- looped about the shaft member 10 toward the center of the shaftmember in operation and thus automatically provides for balanced conditions.

With specific reference to the construction of the discs 50 and 52, it will be noted from FIGURE 3 that the discs have planar opposed inner faces or facing surfaces 51 and 53, respectively, which define the channel 12. The channel is of uniform width between such faces, and this uniformity is positively maintained by virtue of the initial molding and by virtue of thefact that the material used is not subject to shrinkage or the like such as would be encountered with inexpensive wood. Moreover, by virtue of the integral construction of the central shaftrnemher and the discs, there is an initial fixed relation established which cannot be varied, and thus misalignment of these respective elements during assembly is eliminated.

The discs 50 and 52 are symmetrical about the central plane x-x of the core member 24 and each disc has an outer surface including a central hub portion. The hub portion of the disc 56 is designated by the numeral 61 and the hub portion of the disc 52 is designated by the numeral 63. Hub portions 61 and 63 are provided respectively with inwardly extending bores 64 and 66, which bores have a central axis aligned with the central axis of the cone member 24. Preferably, a channel such as designated by the numerals 63 and 7% extends continuously about the respective hub portions 61 and 63. The channels preferably terminate in spaced relation to the peripheral edges 70 and 72 of the respective discs 50 and 52 whereby a peripheral rim portion 74 and 76 exists on each disc.

In the embodiment shown, the peripheral edges 7% and 72 are tapered at a small angle a, peripherally less than inwardly toward the outer surface of each of the discs. This inward taper permits the ready insertion of the peripheral edges '70 and 72 in the respective recesses 34 and 34' of the cover members and 22. Moreover, the tapered construction facilitates exact alignment of the respective components forming the Yo-Yo body 2. The recesses 34 and 34 have a depth d corresponding to the width w of the peripheral rim portions 74 and 76. With this construction when the edges 8i) and 82 of the rim portions 74 and 76 seat on the respective shoulders 36 and 36, the peripheral edge of the respective cover members 30 and 39' is coextensive with the associated inner surface of the corresponding disc. Specifically, as shown in FIGURE 2, edge 38 lies in substantially the same plane as the inner face 51 of the disc member 50 and the edge 38' of the cover member 30 lies in substantially the same plane as the inner face 52.

The diameter of the posts 42 and 42' is substantially the same as the diameter of the bores 64 and 66 whereby to permit frictional insertion of the posts'within the bores. It has been found that the mating cooperation between the posts and the bores and between the recesses and the peripheral edges of the discs affords a tight body construction which is durable in use. However, increased fixing of the components in cooperative association can be achieved by placing a small amount of an epoxy resin or the like in each of the bores 64 and 66 so as to fixedly weld the posts 42 and 42 to the core member 24.

While tapered edges have been shown and described on the core member, it is to be understood that other frictional locking arrangements can be used. For example, the recesses 34 and 34 can be slightly and elliptically distorted whereby when flat edges of the core member cooperate therewith there is a locking cam action. Cooperative distortion of the edges 70 and '72 and the recesses 34 and 34' can also be used as the locking arrangement at the peripheral junction between the components.

The cord 4 on which the Yo-Yo body 2 is mounted is preferably treated with a suitable rosin so as to increase the frictional properties thereof. The use of an all plastic shaft member if}, as explained above, substantially eliminates the frictional surface incorporated in the conventional Yo-Yo constructions, and in order to achieve easy winding of the cord with the instant construction, the rosin treatment or impregnation is desirable so as to fabricate winding of the cord within the channel 12.

With the construction described above satisfactory results are readily obtained. However, in some instances, it has been found that for very extended use of the Yo-Yo in the performance of operations which generate substantial frictional heat, the center post or shaft member It at least, can desirably be made of Teflon (polytetrafiuoroethylene). Teflon withstands heat and friction under the most stringent conditions. Using Teflon, however, at present results in increased costs since the commercial price thereof is substantially greater than the price of other plastics such as mentioned above. Accordingly, where the cost of material is a particularly important factor, the invention contemplates the use of a modified construction.

The modified embodiments The modified constructions provided in accordance herewith correspond in all basic respects with the preferred embodiment described above. Accordingly, in FIGURES 4 through 7, numerals corresponding to those used in FIGURES 1 through 3 are duplicated but in FIG- URES 4 through 7 such numerals are followed by the letter a.

Thus, the Yo-Yo body shown in FIGURE 4 is designated as 2a, the cord as 4a, the loop as 6a, and the channel as 12a. Except as modified, in the following paragraphs, the above description can be read with reference to FIGURES 4 through 6 by merely reading each numeral as if the same were followed by the letter a.

The core member 24a differs from the core member 24 in that the core member 24a includes first and second plastic discs 50 and 52 which are joined together, or positioned in the described spaced relation, by a hollow metal tubular member 100. The member is preferably made of aluminum and has peripherally knurled end sections 162 and 104 disposed on opposite sides of a smooth central section 106. The central section me, as shown in FIGURE 7, preferably is of reduced diameter with respect to the outer diameters of the peripherally knurled sections 102 and 104. However, a uniform passageway or bore extends completely through the member 104 and is centrally disposed with respect to all peripheral surfaces thereon. The tubular member 104 is thus an open-ended hollow tubular member.

In forming the core member 24a of the modified embodiments, the tubular member 100 is preferably supported in any well known manner within a mold adapted to simultaneously form discs 50 and 52 during a molding operation. Then, plastic is fed to the mold, for example, injected therein, and the discs are molded about the tubular member 10% under conventional injection pressures or other molding pressures. The discs 50a and 52a are thus molded to the tubular core member or shaft member 160 with the surfaces of the discs engaging knurled sections 102 and 104 in intimate contact with the projections and recesses of the knurled surfaces.

The core member 24a is thus, as molded, a single piece, just as the core member 24 of the preferred embodiment is a single piece, as molded. Assembly of the modified embodiments is therefore simplified in the same manner as described above.

In addition to having a metal shaft member, the posts of the modified embodiments differ from the posts 42 and 42 of the preferred embodiment. Moreover, the posts 42a and tZa of the embodiment of FIGURE 6 differ from the posts 42b and 42b of the embodiment of FIGURE 5.

Referring first to FIGURE 6, it will be noted that the posts 42a and 42'a have a centrally disposed longitudinally extending bore therein, the bores being numbered and 122 respectively. Each of these bores opens onto the terminal end 44a or 44a as the case may be of its associated post, as well as exteriorly of the respective cover members Ztia and 22a.

With the through-pass bore arrangement which results when the unit of FIGURE 6 is assembled, air inside the shaft member 100 will heat due to friction between such shaft member and the operating spring. As the air heats, the same tends to pass from the interior of the shaft member 100, through the respective bores 120 and 122, thereby effectively ventilating the shaft member. In essence, there is a cross-ventilation which serves to dissipate the heat which is frictionally generated about the 7 shaft member. The ventilation continues as the Yo-Yo moves up and down and/or spins at the bottom of its trajectory.

The outer diameter of the posts 42a and 42'a is substantially the same as the inner diameter of the tubular member 100, i.e., the diameter of the bore 119. Thus,

when the unit of this embodiment is assembled, the free ends of the posts 42a and 42a are frictionally engaged or received within the adjacent underlying ends of the hollow tubular member 100. Thus, just as the ends 44 and 44' of posts 42 and 42' fit within recesses 4 and 66 of core member 24, there is a corresponding fit between end portions 44a and 44a of posts 42a and 42'a with the bore 110 of the hollow tubular member 1% which forms the center of the core member 24a. The bores 120 and 122 in the latter-mentioned posts, as indicated above, permit dissipation-of heat eifectively so that there is no excess heat remaining in the tubular member 100 and so that there is no expansion of the components which would destroy the operational fit therebetweeno Now, turning to the modified embodiment of FIGURE 5, it will be noted that the posts 42b and 42'b terminate short of the outer edges of the shaft or tubular member 100. 'The spacing between the terminal ends 124 and 125 of posts 42b and 42'!) respectively is designated by x. This space is such as to permit the escape of air from within the shaft member 100 to thejair space within 1 the casing or cover members of the Yo-Yo. More spe cifically, air space 126 and 126 exist in each half of the Yo-Yo within the respective cover members 26a and 2211. Since the posts 4212 and 42']; do not fit within the interior of the shaft member 100, the shaft member 100 communicates at opposite ends with the respective spaces 126; and 162. A

Thus, with the construction of FIGURE 5 and the reduced axial length posts 4212 and 42b, the interior of theshaft member 100 communicates with the air spaces thus permitting air to move through the shaft or tubular member 100 whereby to prevent a heat buildup within such shaft or tubular member. This ventilation results in a transfer'of heat from the axle or shaft area to the much larger surface area of the complete assembly and eifective heat dissipation.

The use of the posts 4212 and 42b having short inwardly opening bores 123 and123 respectively, serves to give added rigidity and weight to the outer cover members, or Yo-Yo sides, without interfering with heat dissipation, and yet providing desired balance.

Aside from the provision of a hollow metal central post, preferably aluminum, and the modified construction of the posts projecting inwardly of the cover member, the modified units of FIGURES 4 through 7 are constructed just as the preferred unit, and thus, the outward appearance of the units, as shown in FIGURES l and 4,

is identical. One further difierencehowever, lies in the absence of a concave contour on the periphery of the section 106 corresponding to the concave contour 54 on i the periphery of shaft member 100. If desired, section 106 can be concavely contoured, but such contour is not essential and can be eliminated where cost is a significant factor.

Conclusion After reading the foregoing detailed description, it should be apparent that the objects set forth at the outset of this specification have been successfully achieved.

Accordingly, what is claimed is:

l. A Yo-Yo comprising: first and second cup-shape plastic cover members, each of said cover members having an at least substantially planar and generally circular base and an arcuately-shaped upstanding ring skirt integral with said base, said skirt having an inwardly opening recesss in the interior wall thereof and adjacent the pe-.

ripheral edge thereof remote from said base, said recess terminating at an inwardly extending shoulder disposed 8 p V substantially parallel to said base, and a core member cooperating With .saidfirst and second cover members, said core membercomprising first andsecond plastic discs disposed in parallel spaced apart relation and a central shaft member traversing the space between said discs, said discs. having at least substantially planar opposed inner facing surfaces defining a channel of uniform width therebetween and extending about said shaft member, the periphery of each of said discs being contoured to conformingly and,matingly frictionally engage said wall within said recess in each of said cover members whereby said first and second discs maintain respectively said first and. second cover :members in overlying surrounding relation thereto, said recess being dimensionedto receive the disc with the inner surface of said disc at least sub stantially coextensive with said peripheral edge, each of saidcover members having an inwardly extending post integral therewith, said postsbeing centrally disposed on said base and within said. skirt and terminating in a plane disposed perpendicularly thereof lying between said shoulder and said peripheral edge, each of said discs having an outer surface including a central hub portion, said central hub portionhaving a bore thereindimensioned to frictionally receive one end portion of said posts, the post of each of said cover members frictionally being engaged in the bore of the hub portion of the disc disposedthereunder, and a string looped abouttsaid central shaft member.

2. A plastic Yo-Yo as defined in claim 1 wherein the periphery of each said discs is tapered inwardly toward the outer surface thereof and wherein said interior wall is disposed at least substantially perpendicularly to said base.

3. A plastic Yo-Yo as defined in claim 2 wherein said outer surface of eachof said discs comprises a recessed channel extending uniformly about said central hub portion.

4. A Yo-Yo as defined in claim 1 wherein said core member is plastic and integral with said discs.

5. A Yo-Yo as defined in claim 4 wherein said string is treated with rosin.

6. A Yo-Yo as defined inclaim 1 wherein said central shaft member comprises an open-ended hollow tubular member having peripherally knurled end sections disposed on'opposite sidesof a smooth central section, wherein said tubular member extends through said central hub portion in each of said discs, with said knurled end sections joined to a respective of said discs, wherein said posts are hollow and open, at opposite ends thereof and exteriorly of said cover members, and whereinsaid one end portion of each of saidposts is frictionally received within the adjacent underlying end of said hollow tubular member, said adjacent underlying end providing said bore.

7. A Yo-Yo is defined in claim ,6 wherein said tubular member is aluminum.

8. A Yo-Yo comprising; first and, second, cup-shape plastic cover members, each of said cover members having an atleast substantially planar and generally circular base and an arcuately-shaped upstanding ring skirt integral with said base, said skirt having an inwardly opening recess in the interior Wall thereof and adjacent the peripheral edge thereof remote, from said base, said recess terminating at an inwardly extending shoulder disposed substantially parallel to said base, and a core member cooperating with said first and second cover members, said core member comprising first and second plastic discs disposed in parallel spaced apart relation and a central shaft member traversing the space between said discs, said discs having at least substantially planar opposed innerfacing surfacesdefining a channel of uniform width therebetween and extending aboutsaid shaft member, the periphery of each of said discs being contoured to conformingly and matingly frictionally engage said wall within said recess in each of said cover members whereby said first and second discs maintain respectively said first and second cover members in overlying surrounding relation thereto, said recess being dimensioned to receive the disc with the inner surface of said disc at least substantially coextensive with said peripheral edge, said central shaft member comprising an open-ended hollow tubular member having peripherally knurled end sections disposed on opposite sides of a smooth central section, said peripherally knurled end sections being locked centrally of said disc members respectively, posts extending inwardly centrally of each of said cover members, said posts terminating within the ends of said hollow tubular References Cited by the Examiner UNITED STATES PATENTS 2/53 Stivers et a1. 46-61 6/60 Bond 46-61 RICHARD c. PINKHAM, Primary Examiner. 

1. A YO-YO COMPRISING: FIRST AND SECOND CUP-SHAPE PLASTIC COVER MEMBERS, EACH OF SAID COVER MEMBERS HAVING AN AT LEAST SUBSTANTIALLY PLANAR AND GENERALLY CIRCULAR BASE AND AN ARCUATELY-SHAPED UPSTANDING RING SKIRT INTEGRAL WITH SAID BASE, SAID SKIRT HAVING AN INWARDLY OPENING RECESS IN THE INTERIOR WALL THEREOF AND ADJACENT THE PERIPHERAL EDGE THEREOF REMOTE FROM SAID BASE, SAID RECESS TERMINATING AT AN INWARDLY EXTENDING SHOULDER DISPOSED SUBSTANTIALLY PARALLEL TO SAID BASE, AND A CORE MEMBER COOPERATING WITH SAID FIRST AND SECOND COVER MEMBERS, SAID CORE MEMBER COMPRISING FIRST AND SECOND PLASTIC DISC DISPOSED IN PARALLEL SPACED APART RELATION AND A CENTRAL SHAFT MEMBER TRANSVERSING THE SPACE BETWEEN SAID DISC SAID DISC HAVING AT LEAST SUBSTANTIALLY PLANAR OPPOSED INNER FACING SURFACES DEFINING A CHANNEL OF UNIFORM WIDTH THEREBETWEEN AND EXTENDING ABOUT SAID SHAFT MEMBER, THE PERIPHERY OF EACH OF SIAD DISC BEING CONTOURED TO CONFORMINGLY AND MATINGLY FRICTIONALLY ENGAGE SAID WALL WITHIN SAID RECESS IN EACH OF SAID COVER MEMBERS WHEREBY SAID FIRST AND SECOND DISC MAINTAIN RESPECTIVELY SAID FIRST AND SECOND COVER MEMBERS IN OVERLYING SURROUNDING RELATION THERETO, SAID RECESS BEING DIMENSIONED TO RECEIVE THE DISC WITH THE INNER SURFACE OF SAID DISC AT LEAST SUBSTANTIALLY COEXTENSIVE WITH SAID PERIPHERAL EDGE, EACH OF SAID COVER MEMBERS HAVING AN INWARDLY EXTENDING POST INTEGRAL THEREWITH, SAID POSTS BEING CENTRALLY DISPOSED IN SAID BASE AND WITHIN SAID SKIRT AND TERMINATING IN A PLANE DISPOSED PERPENDICULARLY THEREOF LYING BETWEEN SAID SHOULDER AND SAID PERIPHERAL EDGE, EACH OF SAID DISC HAVING AN OUTER SURFACE INCLUDING A CENTRAL HUB PORTION, SAID CENTRAL HUB PORTION HAVING A BORE THEREIN DIMENSIONED TO FRICTIONALLY RECEIVE ONE END PORTION OF SAID POSTS, THE POST OF EACH OF SAID COVER MEMBERS FRICTIONALLY BEING ENGAGED IN THE BORE OF THE HUB PORTION OF THE DISC DISPOSED THEREUNDER, AND A STRING LOOPED ABOUT SAID CENTRAL SHAFT MEMBER. 